In an LCD (Liquid Crystal Display) or PDP (Plasma Display Panel), TCP (Tape Carrier Package) components, COF (Chip On Film) components, COG (Chip On Glass) components, FPC (Flexible Printed Circuit) boards, other electrical components, mechanical components, optical components and the like are mounted in a mounting area provided in edge portions of a glass substrate of the panel during the manufacture of a display device.
Conventionally, as an example, a method for mounting components 105 to a plurality of mounting areas (mounting positions) 103 in two edge portions 102a, 102b which are located on a longer-edge side and a shorter-edge side of a substrate 101 is now described with reference to a schematic explanatory view shown in FIG. 22. Referring to FIG. 22, as the substrate 101 is carried in, first performed is an ACF applying process for applying anisotropically conductive films (hereinafter, referred to as ACFs) 104 onto each of mounting areas 103 of the substrate 101 having electrodes for electrical junction with component electrodes. Next performed is a component temporary pressure-bonding process for setting and temporarily pressure-bonding the components 105 on the ACFs 104 applied to the individual mounting areas 103 of the substrate 101. This is followed by a final pressure-bonding process for pressure-bonding and fixing (i.e., finally pressure bonding) the components 105 by applying pressing force and heat to the components 105 that have been temporarily pressure-bonded on each of the longer-edge side and shorter-edge side mounting areas 103 of the substrate 101, while electrically connecting the electrodes of the components 105 and the electrodes of the substrate 101, respectively. By these processes being carried out, the components 105 are mounted and then the substrate 101 is carried out toward a succeeding-processing apparatus, as is known as a component mounting method.
Also, a component mounting apparatus for carrying out such component mounting processes as shown above includes an ACF applying device for performing the ACF applying process, a component temporary pressure-bonding device for performing the component temporary pressure-bonding process, a component final pressure-bonding device for performing the component final pressure-bonding process on the longer-edge side and shorter-edge side edge portions, and a conveyor device for conveying the substrate between these working devices (i.e., between the ACF applying device, the component temporary pressure-bonding device and the component final pressure-bonding device). Also, the working devices each include a working unit for performing their respective specified work, and a moving device for, upon reception of the substrate fed from the conveyor device on a substrate holder, positioning the mounting areas of the substrate to their corresponding working positions for the working units (see, e.g., Japanese Patent No. 3781604).
In such a conventional component mounting apparatus as described above, a flat plate-shaped substrate is conveyed with its flat-plate surface horizontal. In each of the working devices, movement and positioning of the substrate is performed by the moving device with a generally central portion of the substrate held from below by a substrate holder, while the working unit performs specified work with top surfaces of the mounting areas in edge portions of the substrate with the edge portions placed and held on a support base.
In addition, as is also known, for conveyance of a large-scale thin plate material such as a glass substrate for use in display panels or the like, the substrate in its generally vertical posture is supported at its lower end edge by a string of rollers so as to be drivable for movement, while a heightwise central portion of the substrate is levitatedly supported from its back face side by a levitational chamber that forms a fluid film of hydrostatic gas against the substrate back face, and moreover a gas stream is jetted diagonally downward from a gas blowoff nozzle toward the substrate top face side, by which the substrate is conveyed with its plate surface kept in a stable posture out of contact (see, e.g., Unexamined Japanese Patent Application Publication No. 2004-123254).
As another known mounting apparatus for mounting components onto a printed circuit board, in order that its horizontal placement area is reduced and double side mounting can be achieved without reversing the substrate, upper and lower side edges of the substrate are movably supported along guide rails, respectively, while an engagement member provided in the moving device is engaged with a rear end of the board to drive the movement of the board. At a specified position, a positioning pin is fitted to a positioning hole provided in the board to perform positioning of the board, and components to be inserted are inserted from the top face side of the board and then fixed by a clinch mechanism set on the back face side (see, e.g., Examined Japanese Utility Model Application No. H2-9599).
In recent years, there is an increasing trend toward larger scales of the substrate for display panel use. Therefore, as in Japanese Patent No. 3781604 or in FIG. 22, with the constitution of the component mounting apparatus for mounting components at edge portions of the substrate, in which the substrate is conveyed in a horizontal posture by the conveyor device and specified work is carried out with the edge portions of the horizontal-postured substrate positioned in specified positions in each of the working devices, there is a problem that the apparatus construction becomes larger-scaled, causing the equipment installation area to be larger. Besides, as another problem, the equipment cost to meet higher-accuracy demands in the component mounting becomes even higher together with the increasing scale of each machinery equipment.
Also, because the substrate has been becoming smaller in plate thickness, the substrate sags by its own weight, as it occurs increasingly at its portions further away from its supported portions (e.g., central portion of the substrate) during movement and positioning of the substrate in the horizontal-postured conveyance of the substrate. In such a case, there arises a need for avoiding interference between the substrate and its surrounding members with each other during the movement and positioning of the substrate or for performing a positioning to correct any sag of the substrate to implement high-accuracy position recognition. This requires more time for movement and positioning of the substrate, making an obstacle to improvement in the production cycle time of component mounting.
Unexamined Japanese Patent Application Publication No. 2004-123254 discloses a constitution in which the substrate is conveyed in a generally vertical posture to reduce the installation area of the conveyor device, and moreover in which the substrate can be conveyed while preventing peripheral edge portions of the substrate from making contact with any members other than the conveyor device and also from meandering. However, the substrate conveyance method disclosed in Unexamined Japanese Patent Application Publication No. 2004-123254 only covers the conveyance of a substrate, and solutions for the above-described problems for the substrate in component mounting apparatuses are neither disclosed nor suggested in Unexamined Japanese Patent Application Publication No. 2004-123254.
Further, Examined Japanese Utility Model Application No. H2-9599 describes a component mounting apparatus for mounting components onto a printed circuit board which is so constituted that components are mounted on the vertical-postured circuit board. However, Examined Japanese Utility Model Application No. H2-9599 only discloses a component mounting method in which the printed circuit board is conveyed with both upper and lower side edges supported by guide rails and, moreover, the board is positioned at a specified position on its conveyance path to perform component mounting. Therefore, the component mounting apparatus disclosed in Examined Japanese Utility Model Application No. H2-9599 is limited to mounting and conveyance of components for boards of high surface rigidity such as printed circuit boards and cannot be applied to substrates on which components are mounted in their edge portions. That is, Examined Japanese Utility Model Application No. H2-9599 neither discloses nor suggests any technique that can be applied to component mounting apparatuses for mounting components in edge portions of a substrate which is low in rigidity because of its large scale and thinness for use in display panels.
Accordingly, an object of the present invention, lying in solving the above-described problems, is to provide a component mounting apparatus and method which allow components to be mounted with high accuracy to edge portions of thin-type substrates or large-scale substrates having low surface rigidity typified by LCDs or PDPs or the like and moreover which allow the productivity of component mounting to be improved.